1. Field of the Invention
This invention relates to a device which enables the terminal part of a paper or cardboard web unwinding from a first reel to be joined in a registered and/or abutting manner to the initial part of a web from a second reel, both the reels being positioned on a reel star. Said joint is made with great precision and with respect to previously printed, punched or sheared parts which are to be further processed.
2. Description of the Prior Art
Reel carriers which provide automatic change-over at full speed and with bonding during motion are known, and are disposed for example in line with printing machines and carry the two reels on an arm-type support which can rotate about a central shaft. Such reel carriers, known as reel stars, enable the web of a first spent reel to be replaced by the web of a new reel, by joining together the two ends by means of an adhesive tape or bonding material disposed essentially in the direction transverse to the web. Said tape is positioned on the initial part of the new reel and adheres to the final part of the spent reel, which is cut to size and pressed on the adhesive part.
However, said method does not allow a joint to be made with respect to a reference position, for printing, or for a sheared edge, as it is executed at full speed.
A very precise joint can be made on suitable devices disposed in line with the plant and provided with a so-called "magazine" which enables the joint to be made under non-moving conditions, while said magazine provides for feeding the plant for example by means of festoon unwinding zones.